We are going to need some more details to help you. Do you use a proxy when in windows? Make and model of computer, Plug in a LAN cable open a terminal by pressing CTRL + ALT + T and enter lspci; ifconfig copy all the output and edit your question to include it.
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Warren HillJul 11 '14 at 11:58

Do you see available networks or not ? And what happens if you run this: sudo /etc/init.d/networking restart ?
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begueradjJul 11 '14 at 12:50

2 Answers
2

I had the same problem with my hp dv6. After a lot of playing around with things and making sure the right drivers were installed, I tried checking my Bios settings and reset to default. Apparently that did the trick for me I guess when they install windows on laptops it changes something in the Bios.

Have you tried my suggestion? when you boot up the computer keep hitting the esc button till it gives you a menu. When the menu is up hit F10 i believe to enter the bios menu. Then restore to default save and exit.
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RipndipJul 11 '14 at 13:58

I did what you said but nothing was change, should I update my bios???
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ghazalehJul 11 '14 at 14:37

Try connecting to the internet directly with an ethernet cable, not through the router. Just disconnect your router from the internet and plug the cable into your computer. Does it work? If it doesn't then there's a problem with the network-manager package.

I suggest to make the flash drive bootable again. Or you can install Ubuntu without connecting to the internet. You can connect later, after the installation. Let me know if it worked. If not i can help you fix your network-manager package

I inistall the ubuntu without connecting to the internet, but I still have problem to connect to the internet. what should i do now?
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ghazalehJul 11 '14 at 14:02

Ok, then you need to reinstall your network manager. This would be really easy if you had internet, but without internet things get a little bit more complicated. Follow the steps in the second answer to this post: askubuntu.com/questions/422928/… Make sure to select the network manager package that corresponds to your version of Ubuntu. Good luck :D
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user301571Jul 23 '14 at 23:00